| Abstrak/Abstract |
Magnetic core–shell CoFe2O4@ZnO nanoparticles have been successfully synthesized by using
coprecipitation method to provide easy separated nanomaterials and high photocatalytic activity
performance. Core–shell nanoparticles with various CoFe2O4-to-ZnO molar ratio (1:2, 1:3, 1:4, 1:5)
have been investigated over x-ray diffraction (XRD), transmission electron microscopy (TEM), UVvisible spectroscopy, and vibrating sample magnetometer. XRD spectra confirm the cubic spinel
ferrite phase structure of CoFe2O4 and the hexagonal wurtzite phase of ZnO. The crystallite size is
found within the range of 14.9–20.6 nm. TEM measurement confirms the good crystallinity of the
samples. The magnetic hysteresis shows that CoFe2O4@ZnO has high saturation magnetization of
about 30 emu g?1 and coercivity of about 300 Oe. Photocatalytic investigation was carried out using
methylene blue (MB) under UV irradiation. Our result yields the enhancement of MB degradation as
ZnO content increases. The maximum photodegradation achieved by the core–shell nanoparticles is
57.2%, 60.5%, 65.5%, and 78.3% for molar ratio of 1:2, 1:3, 1:4, and 1:5, respectively. The
enhancement of MB degradation can be attributed to the formation of internal structure between
CoFe2O4 and ZnO in the form of heterojunction structure. The magnetic properties of core–shell lead
to the easy separation between the magnetic core–shell nanoparticles and the final degraded solution
by permanent magnet. |
